The invention relates to a delivery apparatus for keeping food product warm during transport, and methods for heating food product in a delivery apparatus. In particular, the delivery apparatus includes a heater having a high watt density output and a heat sink in thermal communication with the high watt density heater for release of thermal energy to the food product.
Food products, such as pizza, are frequently prepared and cooked at a store location. The prepared food product is then delivered to a customer at a home or place of business.
A freshly cooked food product may be stored at the store location awaiting a delivery person""s transportation of the food product to the customer. It is common to prepare pizza and store it in a cardboard box. The cardboard box is placed under a heat lamp awaiting pickup by a delivery person. The delivery person then stores the cardboard box in a thermally insulated carrying case for delivery to the consumer. Despite these methods, the product may lose heat during storage and transportation and the temperature of the product may decrease. If the product becomes too cool, it may become unacceptable to a customer. As a result, attention has been directed at techniques for keeping a food product warm after it has been cooked.
The prior art describes delivery apparatus which can be used to keep food items warm during transportation. For example the following U.S. Patents describe such prior art delivery apparatus: U.S. Pat. No. 5,999,699 to Hyatt; U.S. Pat. No. 5,932,129 to Hyatt; U.S. Pat. No. 5,892,202 to Baldwin et al.; U.S. Pat. No. 5,880,435 to Bostic; U.S. Pat. No. 5,884,006 to Frohlich et al.; and U.S. Pat. No. 5,750,962 to Hyatt.
A delivery apparatus for delivering heated items is provided. The delivery apparatus includes a container for holding an article in thermally conductive contact with a heater. The container includes a plurality of walls forming an interior area and an opening. The interior area is constructed for receiving the article and the heater. The opening is constructed for movement of the article in and out of the interior area. The container also includes a flap covering the opening and enclosing the interior area. The heater includes a heating grid constructed to provide an output watt density of at least 2.5 watts per square inch. The heater also includes a heat sink for receiving and storing heat energy from the heating grid. The heater is also provided with a cover and a power cord.
In accordance with another aspect of the invention a delivery apparatus having a controller is provided. The controller includes a central processing unit. A temperature sensor provides information to the central processing unit about the temperature of the heating grid. The controller includes a light source having first and second states of light intensity for providing information to the user about the status of the heating grid. The controller is also provided with an energy storage device for providing electrical energy to the light source.
In accordance with another aspect of the invention a heater constructed for placement within an interior area of a container of a delivery apparatus is provided.
In accordance with a further aspect of the invention a lighting system constructed to be received by a delivery apparatus is provided.
In accordance with another aspect of the invention a method of delivering food is provided.